Press Releases

NEWARK,
Calif., April 3, 2019 — Rain Therapeutics Inc., a privately-held, clinical
stage biotechnology company focused on biomarker-driven, small molecule therapeutics
for patients with cancer, today announced new preclinical data on tarloxotinib
(Tarlox) presented at the American Association for Cancer Research (AACR) Annual
Meeting 2019, held in Atlanta, Georgia from March 29-April 3, 2019. Three
poster presentations detailed: 1) potent in
vitro activity of Tarlox in a variety of EGFR and HER2 mutations, 2) data
demonstrating that STEAP4 expression may serve as an additional biomarker to
predict sensitivity to Tarlox in clinical trials, and 3) results of a
comprehensive set of studies revealing the potential for Tarlox in treating
NRG1 altered cancers.

Key
findings from Rain presentations include:

Tarlox significantly
inhibited tumor growth and regressed tumors in an NRG1 ovarian cancer
patient-derived xenograft model (100% reduction
in tumor size in the group dosed with 48 mg/kg of Tarlox as compared to a 150% increase in tumor size in the control
group).

Tarlox inhibits
proliferation of EGFR and HER2 Exon 20 insertion mutations and
osimertinib-resistant mutations in vitro,
demonstrating potent activity and potential to treat EGFR-driven cancers that
have been unresponsive to the current standard of care.

“Taken
together, these exciting results provide strong evidence for the broad potential
of Tarlox as a targeted cancer therapy,” said Avanish Vellanki, chief executive
officer of Rain Therapeutics. “These data are encouraging as we continue our
Phase 2 clinical trial of Tarlox in non-small cell lung cancer with EGFR exon
20 insertion and HER2 activating mutations, and we are looking forward to
continuing to advance Tarlox through clinical development.”

Copies of the presentation materials can be accessed by visiting the Publications section of the Rain website.

About Rain Therapeutics Inc.

Rain Therapeutics Inc. is a privately-held biotechnology company developing biomarker-driven small molecule therapeutics for patients with cancer. Rain’s lead program, Tarloxotinib, is a hypoxia-activated prodrug of a potent pan-ErbB inhibitor in development as a treatment for non-small cell lung cancer patients with EGFR / ErbB Exon 20 insertion mutations. Rain Therapeutics Inc. has worldwide development and commercialization rights for Tarloxotinib. For more information, visit www.rainthera.com

Data
support expanding clinical development of tarloxotinib to patients with NRG1
fusion and rearranged cancers with a tumor agnostic, basket strategy

NEWARK,
Calif., April 2, 2019 — Rain Therapeutics Inc., a privately-held, clinical
stage biotechnology company focused on biomarker-driven, small molecule therapeutics
for patients with cancer, today announced that it presented new preclinical
data on tarloxotinib (Tarlox), a hypoxia-activated pan-HER inhibitor, in NRG1
fusion positive cancers at the American Association for Cancer Research (AACR) Annual
Meeting 2019, held in Atlanta, Georgia from March 29-April 3, 2019. These data
support a potential addititional indication for Rain. Rain is currently
conducting a Phase 2 clinical trial of Tarlox in EGFR Exon 20 and HER2 mutation
positive non-small cell lung cancer.

“The
activity observed by Tarlox in NRG1 fusion models is very exciting,” said
Avanish Vellanki, chief executive officer of Rain Therapeutics. “The potency of
tarlox observed across various in vitro
and patient-derived animal studies was intuitive as NRG1 tumors rely on
HER-signaling.”

Robert
Doebele, MD, PhD, acting chief science officer of Rain Therapeutics continued, “NRG1
fusion positive cancers resemble NTRK fusion tumors in their addiction to a
single oncogenic driver and their presence across multiple tumor types. Like EGFR
and HER2 exon 20 insertion mutations, NRG1 fusions represent cancers that are
difficult to drug without significant toxicity, hence providing another
opportunity for the hypoxia-activated strategy of tarloxotinib.”

NRG1 encodes the HER3 ligand
neuregulin 1. NRG1 gene fusions are
oncogenic drivers that overexpress the HER3 ligand, leading to
heterodimerization of HER2/HER3 and activation of downstream ERK, PI3K–AKT and
NF-kB pathways.
NRG1 fusions are particularly
enriched in invasive mucinous adenocarcinoma of the lung where they are found
in 27-31% of cases and have also been reported in other cancer types with an
overall incidence of 0.2% across all solid tumors. The preclinical studies presented
at AACR demonstrate, among other significant findings, that Tarlox
significantly inhibited tumor growth and regressed tumors in an NRG1 ovarian
cancer patient-derived xenograft model. There was a 100% reduction in tumor
size in the group dosed with 48 mg/kg of Tarlox as compared to a 150% increase
in tumor size in the control group.

About Rain Therapeutics Inc.

Rain Therapeutics Inc. is a privately-held biotechnology company developing biomarker-driven small molecule therapeutics for patients with cancer. Rain’s lead program, Tarloxotinib, is a hypoxia-activated prodrug of a potent pan-ErbB inhibitor in development as a treatment for non-small cell lung cancer patients with EGFR / ErbB Exon 20 insertion mutations. Rain Therapeutics Inc. has worldwide development and commercialization rights for Tarloxotinib. For more information, visit www.rainthera.com

First
patient dosing comes within ten months of the Series A financing

NEWARK,
Calif., March 19, 2019 — Rain Therapeutics Inc., a privately-held, clinical
stage biotechnology company focused on biomarker-driven, small molecule therapeutics
for patients with cancer, today announced that it has dosed the first patient
in its Phase 2 clinical trial of tarloxotinib (Tarlox). The start of the Phase 2 trial comes within 10
months of the Company announcing its Series A financing.

The open-label RAIN-701 study will evaluate the objective response to Tarlox in lung cancer patients with EGFR Exon 20 insertion or HER2-activating mutations. Tarlox is a hypoxia-activated prodrug of a pan-HER inhibitor.

“The
dosing of the first patient in our Phase 2 trial is an important milestone for
Rain as we advance Tarlox through clinical development,” said Avanish Vellanki,
chief executive officer of Rain Therapeutics. “We continue to be very excited
about the opportunity for Tarlox in all HER-addicted tumors, especially in
patients with limited treatment options.”

The
RAIN-701 study is a Phase 2 open-label trial designed to evaluate the objective
response rate of Tarlox administered once weekly by intravenous administration.
The trial will enroll approximately 40 patients at sites across the U.S.,
Canada and Hong Kong who have been diagnosed with NSCLC confirmed to possess EGFR
exon 20 insertion mutations or HER2-activating mutations.

“Lung
cancer patients with HER-family exon 20 mutations are in great need of
effective and tolerable treatment options,” said lead investigator, Stephen V. Liu,
MD, associate professor of medicine at Georgetown Lombardi Comprehensive Cancer
Center. “As part of our mission, we are committed to engaging in essential
clinical research to develop additional therapies for these patients.”

About Rain Therapeutics Inc.

Rain Therapeutics Inc. is a privately-held biotechnology company developing biomarker-driven small molecule therapeutics for patients with cancer. Rain’s lead program, tarloxotinib, is a hypoxia-activated prodrug of a potent pan-HER tyrosine kinase inhibitor in development as a treatment for non-small cell lung cancer patients. Rain Therapeutics Inc. has worldwide development and commercialization rights for tarloxotinib. For more information, visit www.rainthera.com.

NEWARK,
Calif., February 28, 2019 — Rain Therapeutics Inc., a privately-held, clinical
stage biotechnology company focused on biomarker-driven, small molecule therapeutics
for patients with cancer, today announced presentations of preclinical data from
ongoing studies of Rain’s lead candidate, tarloxotinib, at the American Association
for Cancer Research (AACR) Annual Meeting 2019 being held March 29-April 3,
2019 in Atlanta, Georgia. Poster presentations will feature data detailing in vitro activity of tarloxotinib for a
variety of EGFR/ HER2 mutations and in
vitro and in vivo efficacy in
NRG1 altered cancers, as well as data demonstrating that STEAP4 expression can
serve as an additional biomarker to predict sensitivity to tarloxotinib therapy
in upcoming clinical trials.

Additional details can be found on the conference website. A copy of presentation materials can be accessed by visiting the Science and Publications section of the Rain Therapeutics website after the presentations conclude.

About Rain Therapeutics Inc.

Rain
Therapeutics Inc. is a privately-held biotechnology company developing
biomarker-driven small molecule therapeutics for patients with cancer. Rain’s
lead program, Tarloxotinib, is a hypoxia-activated prodrug of a potent pan-ErbB
inhibitor in development as a treatment for non-small cell lung cancer patients
with EGFR / ErbB Exon 20 insertion mutations. Rain Therapeutics Inc. has
worldwide development and commercialization rights for Tarloxotinib. For more
information, visit www.rainthera.com

FREMONT, Calif., November 6, 2018 — Rain Therapeutics Inc., a privately-held, clinical stage biotechnology company focused on biomarker-driven, small molecule therapeutics for patients with cancer, today announced presentations of preclinical data from ongoing studies of Rain’s lead candidate, tarloxotinib, at the 30th annual EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics being held November 13-16, 2018 in Dublin, Ireland. Rain collaborators at the University of Auckland and the University of Colorado, Denver will present three posters detailing the efficacy of tarloxotinib in preclinical models.

Additional details can be found on the conference website. A copy of presentation materials can be accessed by visiting the Science and Publications section of the Rain Therapeutics website after the presentations conclude.

About Rain Therapeutics Inc.

Rain Therapeutics Inc. is a privately-held biotechnology company developing biomarker-driven small molecule therapeutics for patients with cancer. Rain’s lead program, Tarloxotinib, is a hypoxia-activated prodrug of a potent pan-ErbB inhibitor in development as a treatment for non-small cell lung cancer patients with EGFR / ErbB Exon 20 insertion mutations. Rain Therapeutics Inc. has worldwide development and commercialization rights for Tarloxotinib through an exclusive license from the University of Auckland. For more information, visit www.rainthera.com

About the Translational Therapeutics Team, University of Auckland.

The Translational Therapeutics Team is a oncology research group lead by Associate Professors Adam Patterson and Jeff Smaill that specialize in all aspects of the design and development of hypoxia activated prodrugs. The team is based in the Auckland Cancer Society Research Centre, within the Faculty of Medical and Health Sciences, located at The University of Auckland. Funding support is primarily through the Health Research Council of New Zealand, the Maurice Wilkins Centre for Molecular Biodiversity and Cancer Society Auckland and Northland.

About the Doebele Laboratory, University of Colorado, Denver

The Doebele laboratory at the University of Colorado Anschutz Medical Campus focuses on generating unique patient-derived cancer models, including human cancer cell lines, to study specific oncogene-driven cancers. The lab has successfully defined intrinsic and acquired resistance mechanisms for ALK and ROS1-driven cancers and was the first to identify NTRK1 gene fusions in lung cancer, generating the pre-clinical data that led to the development of TRK inhibitors for lung and other cancers harboring NTRK gene fusions. More recently, the lab has turned to tackling the clinical problem of treating EGFR exon 20 and HER2 exon 20 mutations as well as other HER-family receptor tyrosine kinase-driven cancers. Ultimately, the lab’s goal is to advance personalized medicine through the identification, analysis, and rational targeting of driver oncogenes in cancer in order to improve the clinical outcomes of patients.

Media Contact

FREMONT, Calif. – October 1, 2018 – Rain Therapeutics Inc., a privately-held, clinical stage biotechnology company focused on biomarker-driven, small molecule therapeutics for patients with cancer, announces the addition of Lori Kunkel, M.D., to its scientific advisory board. Dr. Kunkel is a clinical drug development specialist and strategic advisor to targeted and immuno-oncology biotechnology companies with over twenty years of experience in the oncology space.

“We are excited and privileged to have Dr. Kunkel’s help as part of our scientific advisory board,” said Avanish Vellanki, chief executive officer of Rain Therapeutics. “Dr. Kunkel’s decades of experience in clinical oncology drug development will be invaluable as we continue to advance our lead asset, tarloxotinib, and expand our pipeline with additional targeted therapies.”

Dr. Kunkel currently serves on the board of directors of Loxo Oncology, Inc., Curis, Inc., Maverick Therapeutics, Inc.,and Tocagen, Inc. Previously she has served as acting chief medical officer of Loxo Oncology, Inc., chief medical officer of Pharmacyclics, LLC, and Proteolix, Inc. and vice president of clinical development at Xencor, Inc. Earlier in her career she was a clinical scientist at Genentech, where she worked on the development of RITUXAN ®.

“Dr. Kunkel’s approach to drug development is very similar to ours, and Rain will undoubtedly benefit from her perspectives across the various initiatives ongoing at the Company,” said Robert Doebele, M.D., Ph.D., Rain’s co-founder and chairperson of the scientific advisory board.

Prior to her career in biotechnology, Dr. Kunkel spent a decade in academic medicine as a faculty member at the Bone Marrow Transplant Unit in the Division of Hematology/Oncology at University of California, Los Angeles. She received her medical degree from University of Southern California and her bachelor’s degree in biology from University of California, San Diego. She is board certified in internal medicine and has held board certifications in hematology and oncology.

About Rain Therapeutics Inc.

Rain Therapeutics Inc. is a privately-held biotechnology company developing biomarker-driven small molecule therapeutics for patients with cancer. Rain’s lead program, Tarloxotinib, is a hypoxia-activated prodrug of a potent HER inhibitor in development as a treatment for non-small cell lung cancer patients with Exon 20 insertion mutations. Rain Therapeutics Inc. has worldwide development and commercialization rights for Tarloxotinib through an exclusive license from the University of Auckland. For more information, visit www.rainthera.com

FREMONT, Calif., August 22, 2018 — Rain Therapeutics Inc., a privately-held, clinical stage biotechnology company focused on biomarker-driven, small molecule therapeutics for patients with cancer, today announced presentations of preclinical data by its collaborator, the University of Auckland, from ongoing studies of Rain’s lead candidate, tarloxotinib, at the New Zealand Society for Oncology Conference being held August 24-25, 2018 and the Queenstown Molecular Biology Meeting being held August 27-29, 2018, both in Queenstown, NZ. The poster presentations describe the plasma membrane reductase responsible for the activation of tarloxotinib exclusively in hypoxic environments. This unique characteristic increases the specificity of tarloxotinib for cancer cells, making it an ideal candidate for the treatment of EGFR Exon 20 mutation-driven non-small cell lung cancer.

Details on the presentations by the University of Auckland’s Translational Therapeutics team are as follows:

Additional details can be found on the New Zealand Society for Oncology website and the Queenstown Molecular Biology Meeting website. A copy of presentation materials can be accessed by visiting the Science and Publications section of the Rain website after the presentations conclude.

About Rain Therapeutics Inc.

Rain Therapeutics Inc. is a privately-held biotechnology company developing biomarker-driven small molecule therapeutics for patients with cancer. Rain’s lead program, Tarloxotinib, is a hypoxia-activated prodrug of a potent pan-ErbB inhibitor in development as a treatment for non-small cell lung cancer patients with EGFR / ErbB Exon 20 insertion mutations. Rain Therapeutics Inc. has worldwide development and commercialization rights for Tarloxotinib through an exclusive license from the University of Auckland. For more information, visit www.rainthera.com

About the Translational Therapeutics Team, University of Auckland.

The Translational Therapeutics Team is a oncology research group lead by Associate Professors Adam Patterson and Jeff Smaill that specialize in all aspects of the design and development of hypoxia activated prodrugs. The team is based in the Auckland Cancer Society Research Centre, within the Faculty of Medical and Health Sciences, located at The University of Auckland. Funding support is primarily through the Health Research Council of New Zealand, the Maurice Wilkins Centre for Molecular Biodiversity and Cancer Society Auckland and Northland.

FREMONT, Calif., June 5, 2018 — Rain Therapeutics Inc., a privately-held, clinical stage biotechnology company focused on biomarker-driven, small molecule therapeutics for patients with cancer, today announced presentations of preclinical data by its collaborator, the University of Auckland, from ongoing studies of Rain’s lead candidate, Tarloxotinib, at the 5th International Conference on Tumor Microenvironment and Cellular Stress: Signalling Metabolism, Imaging and Therapeutic Targets being held June 8-13, 2018 in Chania, Crete, Greece. An oral presentation will detail the discovery of the plasma membrane reductase responsible for activating Tarloxotinib at the site of the tumor, and a poster presentation will discuss data collected in studies of Tarloxotinib that reveal favorable in vivo properties to be a treatment strategy for patients with EGFR / HER Exon 20 insertion mutations in non-small cell lung cancer (NSCLC).

Details on the presentations by the University of Auckland’s Translational Therapeutics team are as follows:

Additional details can be found on the conference website. A copy of presentation materials can be accessed by visiting the Science and Publications section of the Rain website after the presentations conclude.

About Rain Therapeutics Inc.

Rain Therapeutics Inc. is a privately-held biotechnology company developing biomarker-driven small molecule therapeutics for patients with cancer. Rain’s lead program, Tarloxotinib, is a hypoxia-activated prodrug of a potent pan-ErbB inhibitor in development as a treatment for non-small cell lung cancer patients with EGFR / ErbB Exon 20 insertion mutations. Rain Therapeutics Inc. has worldwide development and commercialization rights for Tarloxotinib through an exclusive license from the University of Auckland. For more information, visit www.rainthera.com

About the Translational Therapeutics Team, University of Auckland.

The Translational Therapeutics Team is a oncology research group lead by Associate Professors Adam Patterson and Jeff Smaill that specialize in all aspects of the design and development of hypoxia activated prodrugs. The team is based in the Auckland Cancer Society Research Centre, within the Faculty of Medical and Health Sciences, located at The University of Auckland. Funding support is primarily through the Health Research Council of New Zealand, the Maurice Wilkins Centre for Molecular Biodiversity and Cancer Society Auckland and Northland.

Media Contact

FREMONT, Calif., May 21, 2018 — Rain Therapeutics Inc., a privately-held, clinical stage biotechnology company focused on biomarker-driven, small molecule therapeutics for patients with cancer, today announced the closing of a tranched Series A financing of $18.4 million. The financing was led by San Francisco-based, Biotechnology Value Fund (BVF) and followed by Perceptive Advisors, Auckland UniServices Limited’s Inventors Fund and other private investors. BVF’s Gorjan Hrustanovic, Ph.D., will join the Rain Board of Directors in conjunction with the financing. The Series A round follows a $1 million convertible note financing completed in late-2017.

Rain plans to use the proceeds to advance the clinical development of its lead program, Tarloxotinib (Tarlox), in patients with EGFR and ErbB Exon 20 insertion mutations in non-small cell lung cancer (NSCLC). The company intends to commence a Phase 2 study in patients with EGFR and ErbB Exon 20 insertion mutations in NSCLC in the first half of 2019.

“With the proceeds from recent financings we can complete a Phase 2, proof-of-concept study and continue to advance Tarloxotinib,” said Avanish Vellanki, Rain’s co-founder and chief executive officer. “Our goal is to provide Exon 20 patients with a novel treatment option that results in strong anti-tumor responses while avoiding the debilitating, dose-limiting EGFR toxicities in the gut and skin that are associated with conventional small molecule inhibitors.”

“Targeting wildtype EGFR, or wildtype EGFR-like tumors has always been very challenging with conventional small molecule inhibitors because of the abundance of EGFR in healthy tissues,” said Robert Doebele, M.D., Ph.D., co-founder of Rain Therapeutics, and associate professor of medicine and director of the Thoracic Oncology Research Initiative at the University of Colorado. “Patients with Exon 20 lung cancer show an addiction to EGFR, however the resemblance of EGFR Exon 20 to EGFR wildtype suggests most conventional strategies will be limited by toxicity. With its novel mechanism of action, Tarlox has the potential to address this inherent, unmet challenge in Exon 20 patients.”

Rain has worldwide development and commercialization rights for Tarlox through an exclusive license to technology developed at the University of Auckland.

About Rain Therapeutics Inc.

Rain Therapeutics Inc. is a privately-held biotechnology company developing biomarker-driven small molecule therapeutics for patients with cancer. Rain’s lead program, Tarloxotinib, is a hypoxia-activated prodrug of a potent pan-ErbB inhibitor in development as a treatment for non-small cell lung cancer patients with EGFR / ErbB Exon 20 insertion mutations. Rain Therapeutics Inc., has worldwide development and commercialization rights for Tarloxotinib through an exclusive license from the University of Auckland. For more information, visit www.rainthera.com